Diseño de Procedimientos Técnicos del Laboratorio de Ensayos en Materiales del CONAVI, según los Requisitos de la Norma INTE-ISO/IEC 17025:2005

Proyecto de Graduación (Licenciatura en Ingeniería en Construcción) Instituto Tecnológico de Costa Rica. Escuela de Ingeniería en Construcción, 2014.This document was developed in order to design all technical procedures for eight laboratory tests involving hydraulic concrete and twelve tests related to stone aggregate, within the CONAVI Material Testing Laboratory, and following both the guidelines from the accreditation process before the Costa Rican Accreditation Entity (ECA) and the guidelines from the norm INTE-ISO/IEC 17025:2005. Also there was developed a technical instructive for laboratory equipment control. Within technical documentation for each test, there were developed tests instructive, registers and technical forms, according to INTECO and ASTM. Furthermore there were designed registers and spreadsheets in order to verify the equipment used in all related tests according to all established specifications. Besides, there were design registers to control the use of ovens, scales, testing machines and neoprene pads. Additionally, there was design a test methods for concrete (temperature, slump, unit weight and compressive strength) and stone aggregate (unit weight, weathering resistance, material finer than N°200 mesh and density, gravity and fine and coarse absorption) validation plan.Instituto Tecnológico de Costa Rica. Escuela de Ingeniería en Construcción

Robust 3D IMU-LIDAR Calibration and Multi Sensor Probabilistic State Estimation

Autonomous robots are highly complex systems. In order to operate in dynamic environments, adaptability in their decision-making algorithms is a must. Thus, the internal and external information that robots obtain from sensors is critical to re-evaluate their decisions in real time. Accuracy is key in this endeavor, both from the hardware side and the modeling point of view. In order to guarantee the highest performance, sensors need to be correctly calibrated. To this end, some parameters are tuned so that the particular realization of a sensor best matches a generalized mathematical model. This step grows in complexity with the integration of multiple sensors, which is generally a requirement in order to cope with the dynamic nature of real world applications. This project aims to deal with the calibration of an inertial measurement unit, or IMU, and a Light Detection and Ranging device, or LiDAR. An offline batch optimization procedure is proposed to optimally estimate the intrinsic and extrinsic parameters of the model. Then, an online state estimation module that makes use of the aforementioned parameters and the fusion of LiDAR-inertial data for local navigation is proposed. Additionally, it incorporates real time corrections to account for the time-varying nature of the model, essential to deal with exposure to continued operation and wear and tear. Keywords: sensor fusion, multi-sensor calibration, factor graphs, batch optimization, Gaussian Processes, state estimation, LiDAR-inertial odometry, Error State Kalman Filter, Normal Distributions Transform

Targeting mitochondria to prevent diclofenac-induced liver toxicity

The objective of the studies described in this thesis was to elucidate the mechanisms of diclofenac-induced toxicity. We focused on mitochondria as the principal target of reactive metabolites of diclofenac. In addition, we investigated several interventions aimed at protecting hepatocytes from diclofenac-induced toxicity, including the intracellular messenger cAMP, the glucose-lowering drug metformin and natural products derived from Opuntia cactus fruit, rich in polyphenols. In Chapter 1, we provide a general introduction to this thesis and an outline of the thesis. Chapter 2 investigates the role of cAMP and downstream cAMP targets like EPACs and protein kinase A in the protection against diclofenac-induced injury in rat hepatocytes. Chapter 3 investigates whether the glucose-lowering drug metformin protects against diclofenacinduced injury and whether any protective effect is related to EPAC. Chapter 4 explores the use of the cactus fruit Opuntia as a treatment for diclofenac induced toxicity, both in vivo and in vitro. Chapter 5 investigates whether steatosis, the accumulation of fat in hepatocytes, affects diclofenac metabolism and toxicity. Finally, Chapter 6 summarizes our results and provides a general discussion and perspective for future studies

Chemical Oxygen Demand Reduction Using the algae Dunaliella primolecta and Chlorella vulgaris

Farm industry wastewater is characterized by high organic materials and by high chemical oxygen demand (COD). Farms with large livestock and poultry operations can be a major source of wastewater thus a major concern for effective environmental and industrial management. Effective environmental and industrial management are high in cost therefor biofuels produced from plants have a potential of replacing a portion of fossil fuel consumption with a renewable efficient alternative. Due to California’s water crisis in the recent years, it is questioned if a biological treatment system that uses algal growth to create renewable energy in the form of biodiesel is able to remove polluting nutrients and greenhouse gases from dairy wastewater

Los días terrenales en "La región más transparente"

1 archivo PDF (10 páginas). fhquadragintatresEn este artículo de ofrecen evidencias derivadas de la teoría del discurso que demuestran que el canon literario mexicano ha logrado una excelente novela, como es “Los días terrenales” cuyas características discursivas la situarían en un nivel igual o superior a la denominada novela de la ciudad, me refiero a “la región más transparente. PALABRAS CLAVE: Narrativa mexicana. Ciudad de México. Carlos Fuentes. José Revueltas. La región más transparente. Los días terrenale

Pericia médica y arte: la otra mirada

La Medicina es la ciencia que está más cerca del hombre. Ningún avatar sociopolítico que haya modificado su organización o su práctica ha podido alterar esta verdad esencial. En el esfuerzo experiencial que el médico debe hacer para aproximarse al hombre, objeto de su quehacer y vocación, se ve necesariamente impelido a intentar un conocimiento holístico de la condición humana, esto es: al humanismo. Y al humanismo médico le debe interesar, sin duda alguna, la actividad creadora a través del Arte, que es el genuino certificado de origen de la Humanidad

Xavier Villaurrutia como crítico de la literatura mexicana

1 archivo PDF (15 páginas). fhtrigintaseptemEl autor describe la actividad del poeta “sin grupo” como crítico en el ámbito literario, particularmente con relación a la literatura mexicana. Con base en una metodología no impresionista, halla algunas limitaciones en la actividad crítica de Villaurrutia, y asimismo, como en cualquier crítico, exaltados amores y odios por algunos autores mexicanos. De la Mora destaca la penuria de Xavier Villaurrutia para referirse a los propios personajes femeninos y la contrastante sagacidad para delimitar a los de otros autores

Presentación : lenguas amerindias y lingüística

1 archivo PDF (10 páginas). fhundequinquagintaEn términos generales, las investigaciones lingüísticas durante el siglo XX dieron prioridad a los estudios de la lengua entendida como un sistema autónomo. Sin embargo, en las últimas décadas del siglo, apareció en el escenario de los estudios de esta disciplina, un marco que concibe las lenguas como un medio de interacción comunicativo entre usuarios Observar los fenómenos de la lengua desde una u otra perspectiva acarrea resultados disímiles, notoriamente, y es sobre este tema que versan los artículos del número 49 de Fuentes Humanísticas